New PassDIY Headphone Amp (now available)

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Well, I do agree with juma for once, to be perfectly honest.

It is difficult to sell an opamp gain stage and a source follower as a headamp that is supposed to stand out from the rest.
There are many of those around, on top of dedicated headphone amp ICs.
And there are also many fully discrete, well published designs, like that from Richard Marsh, e.g.


Cheers,
Patrick
 
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nothing wrong with economic version , made by Big Guys

as I said previously , I would make it even more peasant , invest some in two UPS Accus and simple charger , et voila

take it as Volks B1 Cousin

note - moi not interested neither in this one nor big PL headamp ....... just thinking from regular Greedy Boy boots
 

6L6

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Yes, I've tried the OPA2604 and the LM4562 so far. Both are excellent, and the HPA works well with either. I slightly prefer the 2604, but I'm not a good enough writer to articulate the differences...

The interesting thing is that the circuit is more than clean enough to hear the differences in opamps. That's quite fun. :)

I've put in a Mouser order recently and there are a handful of other opamps I'm going to try.
 
Yes, I've tried the OPA2604 and the LM4562 so far. Both are excellent, and the HPA works well with either. I slightly prefer the 2604, but I'm not a good enough writer to articulate the differences...

The interesting thing is that the circuit is more than clean enough to hear the differences in opamps. That's quite fun. :)

I've put in a Mouser order recently and there are a handful of other opamps I'm going to try.

Looking forward to your impressions. I think I will do the same, it will be fun roll some OPA's.
 
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This amp is meant to be easy to build not really SOTA but it performs quite well. The use of a dual Op amp makes it very easy to build even for a first timer and you can roll in all kinds. Three terminal regulators are also nice and easy to use and work well enough for this kind of project. A satisfying afternoon build.
I do have a day job that takes time, lots of new Pass products entering production and an airplane project 6L6 is helping me out on.;)
 
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I learned few things about PL gang in last few yrs :

- never doubt in their capability to make even better (plenty of reasons for present status)
- never doubt in their good intentions
- they're still young , Greenhorns in fact ......... plenty of time to play with real deal ....... toobz

:clown:

:rofl:
 
Teaser

Just for you Zen Mod..........
 

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6L6

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I had a bit of time to play with the prototypes today...

IMG_0647.jpg

Using LED as a voltage reference, lifting the fixed 15V regulators up by two volts, to give 17V rails. Very easy, very precise.

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Bipolar transistors on the output. (I told yo the bias scheme was really cool...) These are BDW93/94CFP

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Trying a remote mounted pot - this is a 20K Alps RK097 and a cute little eBay board to make soldering easier. Don't let the size fool you, this is a nice pot.

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More opamps being tested, this is a OPA1642 on a SOIC-DIP adapter. Nice. Very nice. :)
 
Looking good, 6L6!:)

I didn't know you could use Darlington transistors in place of MOSFETs.
Is there much difference in DC offset using them?

Also, may I ask where you got your shielded cable from? I've been cutting up some of my inexpensive interconnects, but most seem to have wire inside them about the size of hair.:mad:
 

6L6

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I didn't know you could use Darlington transistors in place of MOSFETs.
Is there much difference in DC offset using them?

As you suspect, yes. So it may not be suggested for the stand build.

But it's still really neat that it works.

Also, may I ask where you got your shielded cable from?

It's Mogami cable for balanced interconnects. Nice stuff - I really like Mogami wire. Good copper, flexible, good shielding, nice materials, easy to work with.

I hope the somewhat alternative heatsink mounting style in the second pic isn't going to be the standard? :D

I suppose if you want to you could... but it's not suggested, no.
:)
 
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